According to the BLS, they set up, operate, or tend forging machines to taper, shape, or form metal or plastic parts.

Median annual pay:$35,480

Number of people who held this job in the US in 2014: 21,600

Predicted number of people who will hold this job in 2024: 17,000

Projected decline: 21.5%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

According to the BLS, they set up, operate, or tend grinding and related tools that remove excess material or burrs from surfaces, sharpen edges or corners, or buff, hone, or polish metal or plastic work pieces.

Median annual pay:$34,150

Number of people who held this job in the US in 2014: 71,400

Predicted number of people who will hold this job in 2024: 55,800

Projected decline: 21.9%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

11. Patternmakers (metal and plastic)

According to the BLS, they lay out, machine, fit, and assemble castings and parts to metal or plastic foundry patterns, core boxes, or match plates.

Median annual pay:$41,670

Number of people who held this job in the US in 2014: 3,800

Predicted number of people who will hold this job in 2024: 2,900

Projected decline: 23.4%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

According to the BLS, they set up, operate, or tend machines to extrude or draw thermoplastic or metal materials into tubes, rods, hoses, wire, bars, or structural shapes.

Median annual pay:$33,800

Number of people who held this job in the US in 2014: 73,400

Predicted number of people who will hold this job in 2024: 55,500

Projected decline: 24.4%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

According to the BLS, they set up, operate, or tend metal or plastic molding, casting, or core-making machines to mold or cast metal or thermoplastic parts or products.

Median annual pay:$30,600

Number of people who held this job in the US in 2014: 129,500

Predicted number of people who will hold this job in 2024: 97,200

Projected decline: 25%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

8. Postmasters and mail superintendents

According to the BLS, they plan, direct, or coordinate operational, administrative, management, and supportive services of a US post office, or coordinate activities of workers engaged in postal and related work in an assigned post office.

Median annual pay:$67,000

Number of people who held this job in the US in 2014: 17,300

Predicted number of people who will hold this job in 2024: 12,800

Projected decline: 26.2%

Why it's declining: The BLS's projected loss of postal worker jobs is due to more reliance on email and online bill pay services and to technological advances that allow for automatic mail sorting. Less postal workers also means less need for supervisory roles.

7. Postal-service clerks

According to the BLS, they perform any combination of tasks in a post office, such as receive letters and parcels; sell postage and revenue stamps, postal cards, and stamped envelopes; fill out and sell money orders; place mail in pigeon holes of a mail rack or in bags; and examine mail for correct postage.

6. Postal-service mail carriers

According to the BLS, they sort mail for delivery and deliver mail on an established route by vehicle or on foot.

Median annual pay:$51,790

Number of people who held this job in the US in 2014: 297,400

Predicted number of people who will hold this job in 2024: 219,400

Projected decline: 26.2%

Why it's declining:According to the BLS, the US postal service is moving to automated "delivery point sequencing" systems that sort letter mail directly. This reduces the amount of time that carriers spend sorting, allowing them to spend more time on the streets delivering mail, thereby increasing the size of their routes and reducing the need to hire more carriers.

5. Pourers and casters (metal)

According to the BLS, they operate hand-controlled mechanisms to pour and regulate the flow of molten metal into molds to produce castings or ingots.

Median annual pay:$34,430

Number of people who held this job in the US in 2014: 9,800

Predicted number of people who will hold this job in 2024: 7,200

Projected decline: 26.6%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

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4. Foundry mold and core makers

According to the BLS, they make or form wax or sand cores or molds used in the production of metal castings in foundries.

Median annual pay: $32,510

Number of people who held this job in the US in 2014: 12,000

Predicted number of people who will hold this job in 2024: 8,700

Projected decline: 27.7%

Why it's declining:According to the BLS, one of the most important factors influencing employment of manual machine setters, operators, and tenders is the high adoption of labor-saving machinery like computer numerically controlled (CNC) machine tools and robots to improve quality and lower production costs.

3. Switchboard operators, including answering service

According to the BLS, they operate telephone business-systems equipment or switchboards to relay incoming, outgoing, and interoffice calls. May supply information to callers and record messages.

According to the BLS, they prepare incoming and outgoing mail for distribution. They also examine, sort, and route mail; load, operate, and occasionally adjust and repair mail processing, sorting, and canceling machinery; keep records of shipments, pouches, and sacks; and perform other duties related to mail handling within the postal service.

Median annual pay:$48,710

Number of people who held this job in the US in 2014: 117,600

Predicted number of people who will hold this job in 2024: 78,000

Projected decline: 33.7%

Why it's declining: The BLS projects the US postal service will need fewer workers to sort mail thanks to new mail sorting technology that can read text and automatically sort, forward, and process mail and the increased use of online bill pay services and email.

1. Telephone operators

According to the BLS, they provide information by accessing alphabetical, geographical, or other directories. They assist customers with special billing requests, such as charges to a third party and credits or refunds for incorrectly dialed numbers or bad connections. May handle emergency calls and assist children or people with physical disabilities to make telephone calls.